Research And Application Of Monitoring System For Large Span Arch

Either during the construction period or during the operation and maintenance period,large span arch bridges disturbed by various factors, such as installation errors, bad weatherand heavy traffic pressure and many more effects cannot be estimated, that bring hugethreats to the quality and safety of the bridges and structures. Therefore, implementation ofreal-time dynamic monitoring has become a necessary way to maintain long span archbridge. And the monitoring system integrated functions of automated monitoring,deformation forecasting and modal parameters identification will become an importantdirection for researching methods to monitor large span arch bridges in the future.The author focuses on the key links and the key technologies to set up a soundmonitoring system that based on GeoCOM, and includes5important parts, such as thedatum of monitoring control network, special factors of monitoring, the methods for dataprocessing, based on time series analysis and modal parameters identification, and theprinciples and processes of exploitation for GeoCOM interface technology and so on. In thepart of monitoring control network, the author discusses two methods of planar datumconversion, and four methods of vertical datum fitting suitable for bridge monitoring; In thepart of special factors of monitoring, the author introduces some principles of triangleelevation and plane coordinate measurement, and focuses on how to eliminate the effects ofatmospheric refraction; In data processing links, the author proposes new "jump point"method to replace the traditional methods to eliminate gross errors, and provides a bettermean to indicate amounts of deformation in A Bridge with examples, that see camberchanges and axis offset as final results; Then, focuses on the steps of establishing astationary time series and illustrates the use of the AR model to predict has good effects,and simultaneously introduces the method of ITD to identify modal parameters; Finally, asthe most central that exploitation based on GeoCOM, the author discusses and researchesthe main principles, the main processes and the detailed functional designs for GeoCOM,that provides a solid theoretical foundation for creating an automated monitoring system.